Bath apparatus



Nov. 27, 1934.

J. S. MARTIN BATH APPARATUS Filed Jan. 8, 1932 3 Sheets-Sheet 1 ATTORNEYS J. S. MARTIN BATH APPARATUS Nov. 27, 1934.

3 Sheets$heet 2 Filed Jan. 8, 1932 INVENTOR.

ATTORNEYS 1 1934- J. s. MARTIN 1,982,261

BATH APPARATUS Filed Jan. 8, 1932 5-Sheets-$heet 5 r g a I mm- QM 67 A v e a {CF76 be 7 1" 6O 81 INVENT OR (\TTORNIYS Patented Nov. 27, 1934 BATH APPARATUS John S. Martin, Atlantic City, N. J., assignor to Hydro-Pneumatic Bath Appliance Company,

Atlantic City,

N. J a. corporation of New Jersey Application January 3, 1932, Serial No. 585,614

Claims.

This invention relates to apparatus which. can be employed to produce a stimulating and invigorating fluid massage together with enforced muscular exercise. This apparatus provides a deep s as well as a superficial massage which is of extreme hydrotherapeutic value and can be applied to any part of the body.

In my prior application Serial No. 566,105, filed September 30, 1931, I have disclosed a fluid maslg sage apparatus embodying a movable injector unit whereby mixed fluid jets of a suitable liquid such as water and a suitable gas such as air can be applied to the body of a patient to produce a vigorous vibratory massage. By moving the in- 15- jector unit, the region of application of the massage to the body can be varied, and if desired, the jets can be placed in action in onedirection of movement and out of action in the other direction' of movement so that the massage acts pro- 20 gressively in a desired direction on the body. The effect of this action is to stimulate circulation in the surface blood vessels in a definite direction, preferably toward the heart. Moreover, the jets are preferably powerful enough to lift the arm or leg of the patient when in action so that as the jets come in and out of action the leg or arm of the patient is caused to rise and fall producing an enforced muscular exercise. The stimulation of circulation, together with muscular exercise, are considered to be probably the most effective treatments for cases of paralyses of one or both of the arms or legs, as in the case of victims of infantile paralysis. The stimulation of circulation by apparatus of this type is shown by the fact that an immediate efiect in infantile paralysis cases is a Warm comfortable condition of the paralyzed parts of the body after the treatment, whereas infantile paralysis victims all suffer from a cold, clammy feeling prior to-the treatment. One of the objects of this invention is to provide a fluid massage and exercising apparatus which will not only massage the desired part of the body of a patient but at the same time can be used to produce muscular exercise of both legs 45. of the patient that is equivalent to natural walking, the treatment which is most desirable to restore the use of the legs in cases of paralysis.

Another object is to provide a pair of movable injector units together withnovel means for co- 5o ordinating the action of the same in properly timed and synchronized relation, whereby the desired action as stated above can be obtained.

Another object is to provide a novel massaging and exercising apparatus embodying a plurality of movable injector units wherein all springs and other mechanical power storing devices are eliminated and movement of the injector units is primarily attested by simple fluid pressure, preferably from the same source which supplies the jets.

A further object is to provide an apparatus of the above type embodying novel valve means for controlling the supply of fluid under pressure to the jets and to the operating means for the units in timed and synchronized relation. 7

A still further objectis to provide an apparatus of the above type embodying fluid pressure operated means for controlling and operating the valve means which regulates the fluid supply. v

Other objects will appear hereinafter as the description of the invention proceeds.

One embodiment of the invention has been illustrated in the accompanying drawings, but it to be expressly understood that said drawings are for purposes of illustration only and are not to be construed as a definition of the limits of the inventiomreferenee being had to the appended claims for this purpose.

In the drawings,

Fig. 1 is a perspective view of an apparatus em bodying the invention;

Fig. 2 is a perspective view of one of the injector units;

Fig. 3 is a perspective detail view of a means for mounting one of the operating tubes or cylinders;

Fig. 4 is a side view of the apparatus, parts being removed for the sake of clearness;

Fig. 5 is a plan view of the apparatus with the top plate removed, said view being partly in section; I,

Fig. 6 is a section taken on the line 6 -6 of Fig. 5; i Fig. '7 is a section taken on the line 7*? of Fig. 5;

Fig. 8 is a section taken on the line 8-8 of Fig. 5; and

Fig. 9 is a section taken on the line 99 of Fig. 7.

In the form shown in the drawings, the apparatus is designed to be used in the ordinary bathtub, to be placed in the bottom thereof preferably underwater. Hence the cover plate 1 is shaped to conform with the bathtub, one end 2 being rounded. Said cover plate 1 is also provided as shown with a plurality of depending ribs-or flanges 3, two of which are side flanges. and is slotted as shown at 4. The other end of the apparatus may be provided with a suitable vertical plate 5 and the whole apparatus is placed in the bottom of the tub as shown in Fig. 4 and is supported by a pair of brackets 6 and 7 resting in the bottom of the tub and preferably shaped to conform therewith. It will be understood, however, that the apparatus may be used in other ways as for example in a large pool and that it may be of any suitable size and hence the shape and size of the cover plate 1, the supporting means therefor, etc., may be varied to suit particular conditions.

Movably mounted beneath the table 1 is a pair of injector units as shown in Fig. 5, and fluid pressure means are provided for reciprocating these units, the jets thereof being aligned with the slots 4 in the table 1. In the form shown, a pair of operating cylinders and pistons therein are employed for moving the injector units in one direction, and the two units are arranged to move in opposite directions and are connected so that the movement of one unit produced by fluid pressure serves to return the other unit to initial or starting position. The operating cylinders, as seen in Fig. 5, comprise tubes 8 and 9 which preferably extend the entire length of the apparatus and are mounted at opposite ends in the supporting brackets 6 and '7 in any suitable manner. For example, at the left hand end of the, apparatus said tubes are supported in openings in the bracket 7 and at the right hand end of the apparatus the tubes are closed by plugs 10 which are threaded to receive bolts 12 passing through openings in the bracket 6. Preferably the bolt holes in the plugs 10 are eccentric so that by rotating the plugs the cylinders 8 and 9 can be lined up.

The two injector units are indicated generally at 13 and 14 in Fig. and are each provided with a piston member which operates in one of the cylinders 8 and 9 and with an additional piston member which operates in one of a pair of outer tubes or cylinders 15 and16 which are likewise supported in openings in the brackets 6 and 7. As shown in Fig. 3, the plugs are split at 11 and are threaded to receive tapered screws 12.

* While any suitable means may be provided for than the cylinder 9, and

mounting the injector units for movment, the support provided by the pistons in the cylinders 8 and in one case and 9 and 16 in the other case will ordinarily be sufficient. As hereinafter described, the cylinders 8 and 9 are not only power cylinders for moving the injector units but also comprise means for supplying a suitable liquid such as water to the injector jets, and the outer cylinders 15 and 16 constitute means for air to the jets. One of the injector units is shown in detail in Figs. 2, 7 and 9, both injector units being the same except that they are arranged for opposite sides of the apparatus. Referring now to these figures, the unit 14 comprises a manifold 17 at one end which manifold is provided with passages 18 and 19 as shown in Fig. 9. At the inner side of the injector unit, the manifold 17 extends freely through a slot 20 formed in the wall of the cylinder 9 (Figs. 5 and 7) and within the cylinder carries an enlarged substantially cylindrical head 21 which is hollow and communicates with the passage 18 of the manifold. Extending from the head 21 is a tube 22 of less diameter at the end of the tube 22 is a piston 23 provided with one or more rings 24 engaging the inner surface of the cylinder 9. Fluid under pressure admitted to the left hand end of the cylinder 9 acts on the head of the piston 23 to force it to the right in said cylinder,

carrying with it the manifold 17 and the entire injector unit 14, and at the same time said fluid passes through an opening 25 in the piston, through the tube 22 and head 21, and into the manifold passage 18.

At the outer side of the injector unit, a slot 26 (Figs. 5 and 7) is formed in the wall of the tube 16 and the manifold extends freely through said slot and carries within said tube an enlarged cylindrical head 28 which is hollow and communicates with the manifold passage 19. A tube 29 extends from said head 28 and terminates in a piston 30 having a ring 31 engaging the inner surface of said tube 16. The left hand end of tube 16 is open to the atmosphere or connected with any suitable source of air, and air entering the tube passes through an opening 32 in the piston 30 and thence through tube 29 and head 28 to the manifold passage 19.

As shown in Figs. 2, 7 and 9, a plurality of pairs of tubes 33 and 34 extend from the manifold 17 and are mounted and held together at their ends by a plate 35. The lower tube 33 of each pair communicates as clearly shown in Fig. 9 with the water passage 18 of the manifold, while the upper tube 34 of each pair communicates with the air passage 19. Each tube 33 is provided with one or more upwardly extending jets 36 which pass through the upper tube 34 and extend into and concentrically with jets 37 in communication with said upper tube. The water under pressure flows from the manifold passage 18 through the tubes 33 and jets 36, and the air flowing through the manifold passage 19 and tubes 34 is entrained in the jets 37, the air and water being discharged therefrom as a powerful mixed jet. Jets of this type are disclosed in my aforesaid application and also in my applications for Letters Patent Serial Nos. 517,088, 517,089 and 517,090, filed February 19, 1931, and the particular form of the jets is not a part of the present invention.

It will be understood that only one of the fluids need be supplied under pressure and that this fluid under pressure may be either water or air, the other fluid being drawn into the apparatus by the suction created by the jets. Whereas in the present case the fluid under pressure is water, the air may be supplied to the tubes 15 and 16 merely by placing them in communication with the atmosphere in any suitable way, as by vertically extending pipes 38 and 39 (Fig. 1) which extend upwardly above the level of the water in the tub. The water under pressure can be supplied from any suitable source and in any suitable way. In some cases the pressure from the water pipes in the tub will be sufficient, and if not, any suitable pumping unit may be employed, the water being led to the apparatus in the form shown through a pipe 40 which is connected to the casing 41 of a valve mechanism to be described hereafter whereby the water is distributed to the cylinders 8 and 9.

When water is supplied under pressure to the cylinder 9, with the parts in the position shown in Fig. 5, the pressure of the water on the piston 23 moves the injector unit 14 toward the right and at the same time the jets are supplied with water and discharge through the slots 4 in the table 1 during movement of the injector unit. Meanwhile the injector unit 13 is returning from the position shown in Fig. 5 to starting position and is moving from right to left, the jets being preferably shut off during this return movement although as to some features of the invention it may be desirable to operate the jets in both directions of moveids ' the unit 14 moves to the J In the form shown,

ment. When the jets are shut on during the re turn movement, it is only necessary to have sufficient water circulation through the jets to :keep the air passages from filling up .with water. A slight pressure is sufficient to maintain this circulation and this pressure is preferably supplied by the movement of the piston 23 in the cylinder 8. In order to avoid a multiplicity of pistons and valve mechanisms, as would be necessary if water pressure were used to move each of the units in both directions, and in order to avoid the use of power storing devices such as springs and the like, means are provided whereby the operative movement of the unit 14 in one direction effects the return movement of the unit 13 in the other direction, and vice 'versa; This may be accomplished by any suitable mechanical connection between the two units whereby they are caused to move simultaneously in opposite directions. In the form shown (Figs. 6 and '7) a gear casing 42 is mounted in any suitable way as by welding on cylinders 8 and 9 and agear 43 is rotatably mounted in said casing by means of a pivot 44. Secured to each of the injector units 13 and 14 by means of brackets 45 is a rack bar 46 which passes slidably through the gear casing 42 and engages the gear 44. Preferably bearing rollers 47 are provided in said casing to support the moving rack bars 46. It will be seen that as right, being driven by water pressure, its rack bar 46 engages and rotates the gear 44 which in turn drives the rack bar 46 of the unit 13, moving the latter to the left. The reverse of this action takes place during the i operative stroke of the unit 13.

In view of the arrangement described above, the valve 41 is of a type adapted to supply water under pressure alternately to the cylinders 8 and 9, the valve being reversed when the j operative stroke of either unit is completed.

Preferably this reversal takes place by means of a diaphragm actuated by Water pressure and having its opposite sides connected to the cylinders 8 and 9, the connections being arranged so that when the operative stroke of either unit is completed, water under pressure is admitted to one or the other side of the diaphragm to bend the same and to shift thevalve. A suitable diaphragm construction is shown in Fig. 6 and comi prises a two-part casing 48 having '-a flexible diaphragm 49 of suitable material such as rubber clamped between the casing sections. The flexible diaphragm is strengthened by rigid disks 50 on either side thereof, said disks being preferably of metal and having rounded peripheries so as to avoid injury to the diaphragm, and a depending post 51 passes through the center of said disks and diaphragm and is secured thereto in any suitable manner, said post passing through a suitable stun'ing box 52 and being connected by means hereafter described with the valve 41. Advantage is taken of the movement of the pistons 23 in the cylinders 8 and 9 to supply water under pressure to the proper side of the diaphragm 49. the walls of the cylinders 8 and 9 are provided with ports 53 and 54 to which are connected pipes 55 and .56, the pipe '55 leading to an opening 57 in the top of the diaphragm casing 48 and the 5:8 in the bottom of the diaphragm casing 48. Preferably these openings in the'diaphragm easing are centrally arranged so that the water pressure is distributed evenly over the entire.

diaphragm surface.

As. the unit 14moves to right from the pipes 56 leading to .anopening position shown in The resulting deflection of the diaphragm is employed to shift the valve 41 so as to shut off the supply of water to the cylinder 9 and, to admit the supply of water to the cylinder 8; The reverse of this action takes place when the unit 13 reaches the end of its operative stroke and its piston 23 uncovers the port 53. The movement of the diaphragm is communicated to the valve in any suitable manner. In the rockshaft 59 is mounted in bearing brackets 60 secured to the casing 48 and is provided with'a rockarm 61 pivoted at 62 to the lower end or the post 51.. At one end of the rockshaft 59 is an upwardly extending lever 63, the end of the shaft being squared as shown in Fig. 8 so that the lever rotates with the shaft. Lever 63 is pivotally connected at 64 with a link 65 which. is in turn pivotally connected at 66 with a valve stem 67 extending into the valve casing 41. Thus as the diaphragm 49 is deflected, the shaft 59 is rocked is moved in the proper direction to effect the desired distribution of water to the cylinders. In case the valve should stick for any reason in starting, the upper end of the lever 63 can be moved by hand in either direction.

The valve employed may be of any suitable type but it is preferred to employ a valve of the type shown in Fig. 8 for reasons to be described. Referring now to Fig. 8, the valve stem 67 is con-, nected with a valve member 68 which seats to the right on a surface 69 of the casing 41 and to the left on a surface 70 of said casing, thereby controlling the supply of. water through valve ports 71 and 72 respectively. The valve casing 41 is secured to the bracket '7 and is provided with a chamber 73 communicating with the cylinder 9 and with a chamber 74 communicating with the cylinder 8. As will be seen from the connections described above, when the port 54 in the cylinder 9 is uncovered the diaphragm 49 is deflected upwardly and the valve 68 is moved tothe right toward its seat 69. Assuming the port '71" to be closed thereby, the water coming from pipe 40 passes through the port '72, chamber 74 and cylinder 8 during the operative stroke of the unit 1 3. During this operative stroke, there is no pressure on either side of the diaphragm 49 because both ports 53 and 54 are covered, the valve 68 being held on its seat by water pressure. When the unit 13 reaches the end of its opera- 49, and the valve 68 the port 72 and opening the port 71 so that the unit 14 begins its operative stroke.

This type of valve and valve operator operates efiiciently and substantially noiselessly to effect the desired operation of the injector units, but certain other advantages are inherent in the construction described. For purposes of explanation, assume that when the unit 14 reaches the end of its operative stroke the valve is operated instantaneously to shut off the pressure to the unit 14 and to admit the pressure to the unit '13. Both units would stop moving and a brief pause would intervene before the unit 13 started its operative stroke and the unit 14 started its return stroke. Now the air passages in the unit 13 have been kept open during the preceding'return stroke by movement of the piston 23 as soon as movement stops in the cylinder 8, and the air passages tendadapted for accomplishing ""1 While the unit 13 1 circulation in the 4- to fill up with water. Similarly the air passages of the unit 14 have been kept open during its operative stroke by the action of the jets and must now be kept open during the return stroke by the movement of piston 23 in cylinder 9. If the valve simultaneously and instantaneously shuts off water pressure to the unit 14 and admits water pressure to the unit 13, the air passages of the unit 14 will tend to fill up with water during the brief pause before movement starts again; and moreover, the unit 13 will tend to start its stroke immediately before suflicient circulation has been built up to render its jets fully effective. The result would be that on starting the operative stroke of a unit an initial travel of one or two inches would take place before the jets became fully operative and there would be some danger of filling up the air passages with water.

Hence it is desirable that the valve should admit water under pressure to both cylinders during the brief interval of pause while the movement of the units is being reversed, thereby maintaining the circulation in the unit which is at the end of its operative stroke to keep the air passages open before return movement starts, and

also allowing an instant for circulation of water to build up through the jets of the unit which is beginning its operative stroke beforemovement begins. The valve described above is particularly these results by adjusting the diaphragm 49 so that its throw under pressure is only sufficient to move the valve to the neutral position shown in Figure 8. Assume for example that the port '71 has been closed has made its operative stroke. When the piston 23 uncovers the port 53, water is admitted to the top of the diaphragm 49 and the valve is shifted to the neutral position so that both ports '71 and '72 are open. This takes place 1 just prior to the completion of the operative stroke of the unit 13. Water continues to flow to the unit 13 to keep the jets and passages thereof open before return movement starts, and at the same time water flows to the unit 14 and builds up a jets thereof, but movement of unit 14 does not start instantly because of the counter pressure on the unit 13. The rush of water to the unit 13 sets up an unbalanced pressure on the valve which causes it to move further 7 to the left into engagement with the seat '70 and to close the port '72 as the unit 14 begins to move on its operative stroke. This insures that the air passages of both units are kept open and that the jets of both units become fully operative before I or immediately when the operative strokes of the units begin.

Preferably means are provided for controlling the speed of movement of the units 13, 14. In the form shown, a by-pass pipe '75 connects the valve chambers '73 and '74, and a suitable regulating valve '76 is inserted in the pipe '75. When the valve '76 is closed, the by-pass '75 has no effect on the operation, but if it should be desired to slow down the movement of the units, the valve '76 is opened an amount sufficient to effect the desired reduction in speed. Assume that the valve 68 is seated to the left and that the unit 14 is making its operative stroke. Opening the by-pass valve '76 will permit water to flow through the pipe '75 from the chamber 73 to the chamber '74 and thus to the cylinder 8. This increases the back pressure against which the unit 13 and its piston 23 must be returned and accordingly slows down the movement of both units an amount depending 1 upon the amount of back pressure so provided.

1 Other m'earis'ma'y also be provided for controlling the speed of movement of the units 13, 14, either in addition to the means above described or as a substitute therefor. In the form shown, an additional speed regulating means is provided which comprises cylinders '77 and '78 mounted below the operating cylinders 8 and 9 and in line with the rack bars 46, said cylinders '77, '78 extending from the left hand end of the apparatus as seen in Figs. 2, 4 and 5 to about the center thereof. Said cylinders '77, '78 may be attached in any suitable manner to the cylinders 8 and 9 or may be mounted independently thereof, the ends of the cylinders at the left hand end of the apparatus being preferably secured to the bracket '7 by means of suitable plugs '79 and 80 which extend through openings in the bracket and into the ends of the cylinders and are provided with flanges secured to the bracket in any suitable manner as by screws 81. On the ends of the rack bars 46 are suitable pistons 82 which operate in the cylinders '77 and '78 and said cylinders are each provided with an opening 83 so positioned that it is uncovered by its associated piston 82 at the end of the operative stroke of the unit 13 or 14. The ends of the cylinders '77, '78 adjacent the bracket '7 are connected by a pipe 84 in which is placed a suitable control valve 85. It will be seen that as the units 13, 14 reciprocate, the rack bars 46 and pistons 82 reciprocate in the cylinders '77, '18, pumping water from the cylinder 7'7 to the other cylinder '78 during the operative stroke of the unit 14, and from the cylinder '78 to the cylinder 7'7 during the operative stroke of the unit 13. As either piston 82 reaches the end of its stroke toward the right, the opening 83 is uncovered to insure that the cylinders are kept full of water. By regulating the valve 85, the amount of resistance offered to the return movement of the units 13 and 14 can be controlled in substantially the same way as it is controlled by the valve '76.

The operation of the apparatus will be clear from the foregoing description and its use may be illustrated in connection with the treatment of cases of paralysis of the legs. The patient sits on the table 1 adjacent the end 2 thereof with the legs lying on the table and extending toward the end plate 5. The supply of water under pressure to the pipe 40 being turned on, the valve. comes into action and the injector units 13 and 14 reciprocate below the table, moving in opposite directions and having their jets operative during movement from left to right. Hence the region of application of the massage is causedto move from the foot or ankle up the leg, stimulating the circulation of blood in the surface blood vessels and forcing the blood through these vessels toward the heart. Moreover, the lifting effect of the jets begins at the foot or ankle and as the injector unit moves, travels up the leg and lifts the entire leg from the table, the knee bending naturally so as to produce a movement equivalent to walking. It will be observed that this action takes place alternately, first one leg being lifted and then the other.

It will be understood that the invention is not restricted to the form described and illus trated in the drawings, thus the supporting table may be of any suitable size and shape and the injector units may be mounted in any suitable manner thereon. If desired, the operating cylinders for the injector units may be mounted separately from the table. Other changes may be made in the form, details of construction and 150 arrangement of the parts without departing from the spirit of the invention and reference is therefore to be had to the appendedclai'ms for a definition of the limits of the invention.

What is claimed is: I v 1. In apparatus of the class described, the combination of a slotted table, a pair of injector units movably mounted beneath said table and having jets discharging through said slots, means for supplying fluid tosaid jets, and means for reciprocating said units, said units moving in opposite directions.

- 2. In apparatus of the class described, the combination of a slotted table, a pair of injector units movably mounted beneath said table and having jets discharging through said slots, means for supplying fluid to said jets, means for reciprocating said units, said units moving in opposite directions, and means for shutting oif the supply of fluid to said jets in one direction of movement of said units.

j 3. In apparatus of the class described, the combination of a slotted table, a pair of injector units movablymounted beneath said table and having jets discharging through said slots, means for supplying fluid to said jets, separate means for moving said units, and a common means for ccntrolling the speed of said units.

4. In apparatus of the class described, the combination of a slotted table, a pair of injector units movably mounted beneath said table and having jets discharging through said slots, means for supplying fluid to said jets, fluid pressure means for reciprocating said units, said units moving in opposite directions, and distributing valve means for admitting fluid under pressure to said fluid pressure means.

5. In apparatus of the class described, the combination of a slotted table, a pair of injector units movably mounted beneath said table and having jets discharging through said slots, means for supplying fluid to said jets, fluid pressure means for moving each of said units, distributing valve means for admitting fluid under pressure alternately to said fluid pressure means, and means actuated by fluid pressure and controlled by movement of said units for controlling said valve.

6. In apparatus of the class described, a slotted ,table, a pair of injector units movably mounted beneath said table and having jets discharging through said slots, means for supplying fluid to said jets, fluid pressure means for moving each of said units in one direction, valve means for distributing fluid under pressure alternately to said fluid pressure means, and mechanical connections between said units whereby movement of one unit on its power stroke causes return movement of the other unit.

7. In apparatus of the class described, a pair of movably mounted injector units, means for supplying fluid to said units, fluid pressure means for moving each of said units, valve means for distributing fluid under pressure alternately to said fluid pressure means, means for automatically operating said valve means, and means for returning said units to starting position.

8. In apparatus of the class described, the combination of a pair of movable injector units, means for supplying fluid to said units, cylinder and piston operatively connected with each unit, valve means for supplying fluid under pressure alternately to said cylinders to move said pistons in one direction, and means operatively connecting said units whereby movement of one 5 unit caused by its piston returns the other unit and its piston to starting position,

9. In apparatus of the class described, the combination of a pair of movable injector units, means for supplying fluid to said units, a cylinder and piston operatively connected with each unit, valve means for supplying fluid under pressure alternately to said cylinders, means for returning said units to starting position, and means for automatically controlling said valve means, said controlling means being actuated by fluid pressure controlled by movement of said units.

1D. In apparatus of the class described, the

combination of a pair of movable injector uni-ts,

cylinder and piston operatively connected each unit, valve for supplying fluid under pressure alternately to said cylinders and their associated injector units, means controlled movement of said units to actuate said valve means, and means for returning said units to starting position.

11. In apparatus of the class described, the combination of a pair of movable injector units, means for supplying fluid to said units, cylinder and piston operatively connected with each unit, valve means for supplying fluid under pressure alternately to cylinders to move said pistons in one direction, means operatively connecting said units whereby movement of one unit in one direction causes movement of the other unit in the opposite direction, and speed. control means comprising means for supplying fiuidat variable pressure to the piston of said last named units to set up a counter pressure.

12. In apparatus of the class described, the combination of a pair of movable injector units, means for supplying fluid to said units, cylinder and piston operatively connected with each unit, each of said pistons having an opening therein, valve means for supplying fluid under pressure alternately to said cylinders, whereby said units are moved in one direction and whereby fluid is admitted through the openings in said pistons to said injector units, and means operatively connecting said units whereby movement in one unit in one direction causes movement of the other unit in the opposite direction.

13. In apparatus of the class described, the combination of a pair of injector units, means for supplying fluid to said units, a cylinder and piston for each of said units, valve means for distributing fluid under pressure alternately to said cylinders, an idler gear, and means on each of said units meshing with opposite sides of said gear.

14. In apparatus of the'class described, the combination of a pair of injector units, a cylinder and piston operatively connected with each of said units, each of said cylinders being provided beyond the range of movement of its piston with a slot and said units having portions slidable in said slots and carrying said pistons, said pistons and portions having passages therein for supplying fluid to said injector units, and means for distributing fluid under pressure to said cylinders.

15. In apparatus of the class described, the combination of a. table having slots therein, a. plurality of pairs of cylinders mounted beneath said table, one cylinder of each pair being disposed centrally oi the table and the other cylinder or" each pair being disposed at one edge of the table, pistons in each of said cylinders, a pair of injector units, means for supplying fluid to said units, each of said injector units being connected to and carried by the pistons of a pair of cylinders, and means for supplying fluid to said cylinders.

16. In apparatus of the class described, the combination of a pair of injector units, means for supplying fluid to said units, a cylinder and piston operatively connected with each unit, a valve for supplying fluid under pressure alternately to said cylinders, a diaphragm operatively connected to said valve, and connections between the opposite sides of said diaphragm and said cylinders and including ports in the cylinder walls arranged to be uncovered by said pistons.

17. In apparatus of the class described, the combination of a pair of injector units, means for supplying fluid to said units, a cylinder and piston operatively connected with each unit, a valve for supplying fluid under pressure alternately to said cylinders, a diaphragm operatively connected to said valve, connections between the opposite sides of said diaphragm and said cylinders and including ports in the cylinder walls arranged to be uncovered by said pistons, and means operatively connecting said units whereby movement of one unit in one direction causes movement of the other unit in the opposite direction.

18. In apparatus of the class described, the combination of a pair of injector units, means for supplying fluid to said units, a cylinder and piston operatively connected with each unit, a valve movable between two positions for distributing fluid under pressure alternately to said cylinders, and means controlled by movement of said units for actuating said valve to an intermediate position, said valve being thereafter moved to one of said two positions by fluid pressure whereby fluid is admitted to both cylinders during a time interval between successive closed positions of said valve.

19. In apparatus of the class described, the combination of a pair of injector units, means for supplying fluid to said units, a cylinder and piston operatively connected with each unit, a valve for distributing fluid under pressure alternately to said cylinders, means connecting said units whereby movement of one unit in one direction causes movement of the other unit in the other direction, a by-pass connecting opposite sides of said valve, and a valve for controlling said by-pass.

20. In apparatus of the class described, the combination of a pair of spaced parallel cylinders, pistons and piston rods slidable therein, said pistons having openings therein communicating with passages in said piston rods, an injector unit adapted to discharge mixed fluid jets, said injector unit being carried by said piston rods and having passages communicating with said first named passages, means for supplying fluids to said cylinders and through said passages to said injector unit, at least one of said fluids being under pressure to move said injector unit in one direction, and means for moving said injector unit in the other direction.

JOHN S. MARTIN. 

